This has got to be a typo:
About 91 percent of PCs today are infected with spyware programs that send information from your PC to an unauthorized third party.
NCSA (National Cyber Security Alliance, not the National Center for Supercomputing Applications of Mosaic fame) Chairman Ken Watson quoted by CNET in Study: Consumers take cyberattacks lightly.
That’s a staggering number, and I hope it’s supposed to be 19. Even so, considering how many computers there are in the world, it’s still a staggering number.
Spyware, viruses and worse are out there, and they’re all over both business and home computers. It’s worth checking out the NCSA’s website, staysafeonline.info, as well as others like CERT‘s page on Home Network Security, the US-CERT website, or the FTC‘s guide to Consumer Information Security (though I can’t quite get past the turtle logo on that one).